/*
 * $Header: /home/cvs/jakarta-tomcat-4.0/catalina/src/share/org/apache/catalina/util/Base64.java,v
 * 1.4 2001/09/04 21:49:55 craigmcc Exp $ $Revision: 1.4 $ $Date: 2001/09/04 21:49:55 $
 * ==================================================================== The Apache Software License,
 * Version 1.1 Copyright (c) 1999 The Apache Software Foundation. All rights reserved.
 * Redistribution and use in source and binary forms, with or without modification, are permitted
 * provided that the following conditions are met: 1. Redistributions of source code must retain the
 * above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions
 * in binary form must reproduce the above copyright notice, this list of conditions and the
 * following disclaimer in the documentation and/or other materials provided with the distribution.
 * 3. The end-user documentation included with the redistribution, if any, must include the
 * following acknowlegement: "This product includes software developed by the Apache Software
 * Foundation (http://www.apache.org/)." Alternately, this acknowlegement may appear in the software
 * itself, if and wherever such third-party acknowlegements normally appear. 4. The names
 * "The Jakarta Project", "Tomcat", and "Apache Software Foundation" must not be used to endorse or
 * promote products derived from this software without prior written permission. For written
 * permission, please contact apache@apache.org. 5. Products derived from this software may not be
 * called "Apache" nor may "Apache" appear in their names without prior written permission of the
 * Apache Group. THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR ITS
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
 * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ==================================================================== This software consists of
 * voluntary contributions made by many individuals on behalf of the Apache Software Foundation. For
 * more information on the Apache Software Foundation, please see <http://www.apache.org/>.
 * [Additional notices, if required by prior licensing conditions]
 */

package org.apache.catalina.util;

import java.text.FieldPosition;
import java.util.Date;

import javax.servlet.http.Cookie;

// XXX use only one Date instance/request, reuse it.

/**
 * Cookie utils - generate cookie header, etc
 *
 * @author Original Author Unknown
 * @author duncan@eng.sun.com
 */
public class CookieTools {

    /**
     * Return the header name to set the cookie, based on cookie version
     * 
     * @param cookie
     * @return
     */
    public static String getCookieHeaderName(Cookie cookie) {
        int version = cookie.getVersion();

        if (version == 1) {
            return "Set-Cookie2";
        } else {
            return "Set-Cookie";
        }
    }

    /**
     * Return the header value used to set this cookie
     * 
     * @param cookie
     * @return
     */
    public static String getCookieHeaderValue(Cookie cookie) {
        StringBuffer buf = new StringBuffer();
        getCookieHeaderValue(cookie, buf);
        return buf.toString();
    }

    public static void getCookieHeaderValue(Cookie cookie, StringBuffer buf) {
        int version = cookie.getVersion();

        // this part is the same for all cookies

        String name = cookie.getName();
        if (name == null) {
            name = "";
        }
        String value = cookie.getValue();
        if (value == null) {
            value = "";
        }

        buf.append(name);
        buf.append("=");
        maybeQuote(version, buf, value);

        // add version 1 specific information
        if (version == 1) {
            // Version=1 ... required
            buf.append(";Version=1");

            // Comment=comment
            if (cookie.getComment() != null) {
                buf.append(";Comment=");
                maybeQuote(version, buf, cookie.getComment());
            }
        }

        // add domain information, if present

        if (cookie.getDomain() != null) {
            buf.append(";Domain=");
            maybeQuote(version, buf, cookie.getDomain());
        }

        // Max-Age=secs/Discard ... or use old "Expires" format
        if (cookie.getMaxAge() >= 0) {
            if (version == 0) {
                buf.append(";Expires=");
                if (cookie.getMaxAge() == 0) {
                    DateTool.oldCookieFormat.format(new Date(10000), buf, new FieldPosition(0));
                } else {
                    DateTool.oldCookieFormat.format(
                            new Date(System.currentTimeMillis() + cookie.getMaxAge() * 1000L),
                            buf, new FieldPosition(0));
                }
            } else {
                buf.append(";Max-Age=");
                buf.append(cookie.getMaxAge());
            }
        } else if (version == 1) {
            buf.append(";Discard");

            // Path=path
            if (cookie.getPath() != null) {
                buf.append(";Path=");
                maybeQuote(version, buf, cookie.getPath());
            }

            // Secure
            if (cookie.getSecure()) {
                buf.append(";Secure");
            }
        }
    }

    static void maybeQuote(int version, StringBuffer buf, String value) {
        if (version == 0 || isToken(value)) {
            buf.append(value);
        } else {
            buf.append('"');
            buf.append(value);
            buf.append('"');
        }
    }

    /**
     * from RFC 2068, token special case character
     */
    private static final String tspecials = "()<>@,;:\\\"/[]?={} \t";

    /**
     * Return true if the string count as an HTTP/1.1 "token"
     * 
     * @param value
     * @return
     */
    private static boolean isToken(String value) {
        int len = value.length();

        for (int i = 0; i < len; i++) {
            char c = value.charAt(i);

            if (c < 0x20 || c >= 0x7f || tspecials.indexOf(c) != -1) {
                return false;
            }
        }
        return true;
    }
}
